medical terminology ch 11 (last one!): special senses of the eyes and ears

ophthalmology

diagnosis and treatment of eye disorders, including examinations, prescribing corrective lenses, corrective eye surgeries

ophthalmologist vs optometrist vs optician

ophthalmologist is an MD and specialist in ophthalmology; optometrists and opticians provide corrective lenses and are not MDs

otolaryngology

medical and surgical management of patients with disorders of ENT and related structures of the head and neck

otolaryngologists/ENT physicians vs audiologists

otolaryngologists or ENT physicians are MD specialists who treat disorders of sinuses, sleep disorders, hearing loss; audiologists are not MDs but treat hearing loss

function and structure of eyes

eyes and accessory structures are receptor organs that provide vision by detecting stimuli and transmitting it to the brain; they are housed in the bony cavity AKA orbit

three layers of the eye

-fibrous tunic (outer layer with posterior sclera that is avascular with pain receptors and the anterior cornea, joined by an opening known as the canal of Schlemm)

-vascular tunic, AKA uvea (composed of the vascular choroid that prevents glare, ciliary body which is a muscle, and iris which is the colored portion of eye)

-sensory tunic AKA retina (lines posterior 2/3s of eyeball with rods for light presence and cones for color concentrated in the fovea)

where does the optic nerve exit?

through the sclera at the posterior of the eyeball

function and structure of the lacrimal gland and lacrimal sac

the lacrimal gland is located above the outer corner of each eye and produces tears; the lacrimal sac collects tears and drains them into the nasolacrimal duct

blephar/o

eyelid

chromat/o

color

conjunctiv/o

conjunctiva

choroid/o

choroid (thin vascular layer of the eye between the retina and sclera)

corne/o

cornea

cor/o, core/o, pupill/o

pupil

dacry/o, lacrim/o

tear, lacrimal apparatus (duct, sac, or gland)

dipl/o

double

irid/o

iris

kerat/o

horny tissue, hard, cornea

ocul/o, ophthalm/o

eye

opt/o

eye, vision

retin/o

retina

scler/o

hardening, sclera (white of the eye)

-opia, -opsia

vision

-ptosis

prolapse, downward displacement

-tropia

turning

function of ears

ears are receptor organs that enable hearing and balance

3 divisions of the ear

outer, middle, and inner ear; outer and middle ear conduct sound waves through the ear; inner ear receives and transmits them to the brain and maintains balance and equilibrium

parts of the external ear

auricle (directs sound waves), ear canal, tympanic membrane (vibrates)

parts of the middle ear

malleus, incus, and stapes; eustachian tube (leads from middle ear to nasopharynx and permits air to enter or leave the middle ear cavity)

parts of the inner ear

cochlea (for hearing), semicircular canals (for equilibrium), vestibule (joins the two)

acous/o, audi/o, audit/o

hearing

myring/o, tympan/o

tympanic membrane (eardrum)

ot/o

ear

salping/o

tube (usually fallopian or eustachian)

-acusis

hearing

ARMD, AMD

age-related macular degeneration

ECCE

extracapsular cataract extraction

IOL

intraocular lens

IOP

intraocular pressure

LASIK

laser-assisted in situ keratomileusis

OD

doctor of optometry

RK

radial keratotomy

VA

visual acuity

AC

air conduction

BC

bone conduction

ENT

eat, nose, throat

IVFA

intravenous fluorescein angiography

NIHL

noise-induced hearing loss

OM

otitis media

PE

physical eczema, pulmonary embolism, pressure-equalizing (tube)

URI

upper respiratory infection

achromatopsia

congenital deficiency in color perception AKA color blindness

astigmatism (Ast)

defective curvature of the cornea and lens which causes light rays to focus unevenly over the retina rather than being focused on a single point, resulting in a distorted image

cataract

degenerative disease in which the lens of the eye becomes progressively cloudy, causing decreased vision

diabetic retinopathy

retinal damage marked by aneurysmal dilation and bleeding of blood vessels or formation of new blood vessels causing visual changes

glaucoma

condition in which aqueous humor fails to drain properly and accumulates in the anterior chamber of the eye, causing elevated IOP

-Open-angle: most common form, results from degenerative changes that cause congestion and reduce flow of aqueous humor through canal of Schlemm

-Closed-angle: caused by anatomically narrow angle between iris and cornea which prevents outflow of aqueous humor from eye into lymphatic system, causing sudden increase in IOP

hordeolum

small purulent inflammatory infection of sebaceous gland of the eyelid; AKA stye

macular degeneration (MD)

breakdown of tissues in the macula resulting in loss of central vision; blood and fluids leak from intraocular vessels and destroy visual cells

photophobia

unusual intolerance and sensitivity to light

retinal detachment

separation of retina from choroid; disrupts vision and results in blindness if not repaired

strabismus

muscular eye disorder where eyes turn from the normal position so they deviate in different directions

-Esotropia - strabismus where there is deviation of visual axis of one eye toward other eye, results in diplopia, AKA cross-eye and convergent strabismus

-Exotropia - strabismus where there is deviation of visual axis of one away away from other eye, results in diplopia, AKA wall-eye and divergent strabismus

acoustic neuroma

benign tumor that develops from the 8th cranial nerve and grows within the auditory canal

hearing loss

decreased ability to perceive sounds compared to normal

-Anacusis - total deafness

-Conductive - hearing loss from any condition that prevents sound waves from being transmitted to auditory receptors

-Noise-induced - results from exposure to very loud sounds

-Sensorineural - hearing loss caused by permanent or temporary damage to sensory cells or nerve fibers of inner ear

ménière disease

rare disorder of unknown etiology within the labyrinth of the inner ear that can lead to progressive hearing loss

otitis externa

infection of external auditory canal

otitis media

inflammation of middle ear, commonly the result of an URI

-Scrous - noninfectious inflammation of middle ear with accumulation of serum

-Suppurative - inflammation of middle ear with pus formation

otosclerosis

ossification in the bony labyrinth that leads to progressive deafness

presbycusis

impairment of hearing that results from the aging process

tinnitus

ringing or tinkling noise heard constantly or intermittently in one or both ears, even in a quiet environment

vertigo

sensation of moving around in space or the feeling of spinning or dizziness

slit-lamp examination

eye evaluation that provides a stereoscopic (3D) view of the eye's interior using a binocular microscope (slit lamp) of high-intensity light source to accentuate the anatomical structure of the eye

tomometry

test to measured increased IOP to detect glaucoma

intravenous fluorescein angiography (IVFA)

imaging technique to study retinal blood vessels and the circulation of blood in the retina using photographs of the retina after injection of fluorescent dye

visual acuity (VA) test

exam that identifies the smallest letters that can be correctly read on standardized Snellen vision chart from 20 feet

audiometry

test that measures hearing acuity at various sound frequencies

otoscopy

visual exam of the external auditory canal and tympanic membrane using an otoscope

-Pneumatic - otoscopic procedure that assesses ability of the tympanic membrane to move in response to a change in air pressure

tuning fork test

hearing test that uses a tuning fork that is struck then placed against/near bones on side of head to assess nerve and bone conduction of sound

-Rinne - evaluates bone conduction of sound in one ear at a time

-Weber - evaluated both ears at the same time

cataract surgery

excision of lens affected by a cataract

-Extracapsular cataract extraction (ECCE) - excision of anterior segment of lens capsule along with the lens, allowing for insertion of an IOL implant

-Phacoemulsification - excision of lens by inserting ultrasonic probe whose sound waves break lens into tiny particles that are suctioned out of the eye, then the IOL is implanted

corneal transplant

surgical transplantation of donor cornea from cadaver into eye of recipient; AKA keratoplasty

iridectomy

excision of a portion of the iris to relieve IOP in glaucoma

laser photocoagulation

use of an argon laser to treat diabetic retinopathy by sealing leaking blood vessels in the retina

LASIK (laser-assisted in situ keratomileusis)

use of excimer laser to correct errors of refraction such as myopia, hyperopia, and astigmatism, by reshaping the cornea and improving visual acuity

cochlear implant

electronic transmitter surgically implanted into the cochlea of a deaf person to restore hearing